Adjustable shelf



FIG. 1 is a top isometric view of an adjustable shelf showing my new design.

FIG. 2 is a bottom isometric view thereof.

FIG. 3 is a right front side elevation view thereof.

FIG. 4 is a left rear side elevation view thereof.

FIG. 5 is left front side elevation view thereof.

FIG. 6 is right rear side elevation view thereof.

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof. 

CLAIM The ornamental design for an adjustable shelf, as shown and described. 